title: Follicular fluid insulin like growth factor-1 (FF IGF-1) is a biochemical marker of embryo quality and implantation rates in in vitro fertilization cycles.
abstract: BACKGROUND
  Insulin-like growth factor-1 (IGF-1) has been reported to play a role in human follicular and embryonic development. However, earlier studies carried out mostly in animal models or in culture mediums supplemented with IGF-1 have been unable to directly link IGF-1 with embryo quality. Results correlating IGF-1 with pregnancy outcome have also been ambiguous so far.
  
  
  OBJECTIVE
  The aim of this study is to find if in situ follicular-fluid level of IGF-1 is predictive of embryo quality and implantation rates in in vitro fertilization (IVF) cycles.
  
  
  METHODS
  Prospective study involving 120 cycles of conventional IVF-embryo transfer in infertile women.
  
  
  METHODS
  IGF-1 concentrations were estimated in pooled follicular-fluid on the day of oocyte-pickup. Embryo quality was assessed daily at different developmental stages. Cycles were sorted into low and high follicular fluid insulin-like growth factor-1 (FF IGF-1) groups according to the median value of measurement. Embryo quality, clinical pregnancy and implantation rate were the main outcome measures.
  
  
  METHODS
  Graph-pad Prism 5 statistical package.
  
  
  RESULTS
  FF IGF-1 correlates with embryo quality (Pearson r = 0.3894, r (2) = 0.1516, P > 0.0001) and clinical pregnancy (Pearson r = 0.5972, r (2) = 0.36, P > 0.0001). High FF IGF-1 group shows significantly higher rates of fertilization, cleavage, blastocyst formation and top grade embryos compared with low FF IGF-1 group. Clinical pregnancy rates (38.33 vs. 20%, P = 0.0272) and embryo implantation rates (21.6 vs. 10.32%, P = 0.0152) are also significantly higher in the high versus low FF IGF-1 group. Threshold value of FF IGF-1 for clinical pregnancy is <58.50 ng/mg protein (receiver operating characteristics AUC : 0.85 ± 0.03, 95% CI: 0.78-0.91).
  
  
  CONCLUSIONS
  FF IGF-1 is a plausible biochemical marker of embryo quality and implantation rate and correlates with clinical pregnancy rates in conventional IVF cycles.
authors.affiliation: Department of Embryology and Biochemistry Research Laboratory, Vaunshdhara Clinic and Assisted Conception Centre, Nagpur, Maharashtra, India.
authors.forename: Bindu N
authors.initials: BN
authors.lastname: Mehta
authors.forename: Natachandra M
authors.initials: NM
authors.lastname: Chimote
authors.forename: Meena N
authors.initials: MN
authors.lastname: Chimote
authors.forename: Nishad N
authors.initials: NN
authors.lastname: Chimote
authors.forename: Nirmalendu M
authors.initials: NM
authors.lastname: Nath
keywords: Clinical pregnancy; FF IGF-1; IVF cycles; embryo quality; implantation rate